Cylinder for internal-combustion engines



March 24, 1925. 1,531,165

G. S. WILKINSON- CYLINDER FOR INTERNAL COMBUSTION ENGINES Fild Dee. 29,1922 IHIGIIIOH any? , Patented Mar. 24, 1925.

UNITED STATES I 1,531,1 3v PATENT OFFICE.

GEORGE SHAKESPEARE WILKINSON, OF LONDON, ENGLAND, ASSIGNOR TO D. NAPIER&

SON LIMITED, OF LONDON, ENGLAND, A COMPANY OF GREAT BRITAIN.

' CYLINDER FOR INTERNAL-COMBUSTION ENGINES.

Application filed December 29, 1922. Serial No. 609,738;

To all whom z't may concern:

Be it known that I, GEORGE SHAKESPEARE WILKINSON, a subject of the Kingof England, and residing at London, in En land,

5 have invented certain new and usefu Improvements in Cylinders forInternal-Gombustion Engines, of which the following is a specification.

The invention relates to cylinders .for internal combustion engines moreparticular-v ly air-cooled cylinders of that type in which an open-endedcylinder formed of steel or similar metal has mounted. on its end a headconstructed of aluminium or aluminium alloy and has for its object toeffect certain improvements in the juncture between the head and thecylinder.

In air-cooled cylinders of the type in question owing to the'diflerentcoefficients of expansion ofthe metals of which the cylinder and headare formed, there is a difliculty in maintaining a tight joint betweenthese parts and the present invention is directed to providing aconstruction of such a nature that a tight joint will be ensured while,if desired, the construction will permit of the head being readilydetached.

According to this invention a head formed of metal having a coefiicientof expansion H dilferent from" that of the metal of which the open-endedcylinder is formed is screwed or otherwise mounted on the cylinder so asto enclose the end of the latter. A ring formed of a metal which iseither the same as that of the cylinder or has a similar or greatercoeflicient of expansion is mounted and fits closely on that part of thehead which surrounds the end of the cylinder.

Thus that portion 'of the head which en- 40 gages the end ot thecylinder lies between the cylinder and the separate ring, the latterbeing screwed or otherwise fixed on to the head. The head may thus beprovided with an annular flange internally ,sorewawthreaded to engagethe correspondingly screwthreaded end of the 'cylipder. The ringwhichflts closely on and around the head flange is constructed,together'with this flange, so that the engaging portions of thesemembers are either plain or wholly or partially coned and screwthreaded.In this way the flange or corresponding portion of the head whichsurrounds the end of the cylinder is so engaged by the separate ring asto be clamped by this ring on to the en of the cylinder and in this waya tight joint is maintained between the head and the cylinder since thecylinder and the ring will expand equally.

The invention may be carried out in practice in various ways but thefollowing may be instanced as alternative constructions that may beadopted.

In each case the cylinder A, which is vpreferably formed of steel,carries radiating fins A except at or near its upper end, the scylinderbeing formed with both ends open. The exterior of the upper or outer endof the cylinder is screwthreaded as at A and on to the cylinder isscrewed the head B 70 whichmay be made of aluminium or aluminium alloyand is given a suitable structures with external radiating fins B. Thepart of the cylinder head which screws on to and engages the end of thecylinder is in effect an annular flange B but this part may beconstructed in various ways as found desirable.

In the accompanying drawings,

Figure 1 shows in vertical section one form of'cylinder head andlockingring according to this invention, and

Figures 2 and 3 show also in vertical sec- 1 tion modified forms oflocking ring and that portion of the cylinder head with which theycooperate.

In the arrangement shown in Figure 1 the locking of the head B onthecylinder A is effected as follows. The exterior of the head flange Bwhich engages the end of the cylinder is formed conical at'its upper endC but for its remaining length it is formed parallel to the cylinder andscrewthreaded as at G. A ring D constructed for example of the samesteel as the cylinder and conveniently provided on its exterior withradiating fins D is internally coned and screwthreaded to engage theexterior of the head flange B. When this ring is in position and screwedup, the flange B will be clamped or held between the ring D and thecylinder, and since both these partsare formed of metal or metals havingthe same or substantially the same coefficient of expansion theexpansion of the interposed 105 metal of-the head will be controlled anda tight joint between the head and the cylinder maintained."

In an alternative arrangement shown in Figures 2 and 3 the exterior ofthe head 110 of the conicity of the exteriorof the head flange either inthis case or in the arrangement described above may vary as founddesirable.

Yet again the exterior of the head flange ;may be smooth and parallelwith the inte rior of the cylinder, the clamping ring being pressed orshrunk into place on the head ange.

Other arrangements may be adopted it desired but in each instance it isto be noted that the looking or clamping ring is carried entirely on theflange or other part of the head which engages and encloses the endofthe cylinder so that the ring is not in contact with the cylinder andthe metal of the head flange is disposed and held between the wall ofthe cylinder and the interior of the ring.

Suflicient clearance is leftbetween the end of the head flange and theadjacent. radiating rib or ribs on the cylinder so as to facilitate theplacing of the ring in position or its removal if it is desired todetach the head from the cylinder.

As mentioned above, the separate ring may be formed of a metal which isthe same as or similarto that of which the cylinder ltself is formed. Insome cases, however,

in place of the ring metal being suchv as. to

ring'these annuli being formed so. that they have the same orapproximately the same coefficient of expansion. as the cylinder metal,there may be employed in the structure of the rin cient 0 expansion thanthe cylinder metal. This may be desirable in view of the cylinder beingsubjected to a higher temperature than the outer ring. It is alsodesirable to determine the expansion of the ring with relation to thethickness of the metal .in the head flange which is interposedibetweenthe ring and the cylinder. In any case it is the object of the inventionto constrain the head flange betweenconcentric metal .annuli, namely,the end of the cylinder and the I will expand in a substantially similarmanner and thus counteract the tendency of the head flange to expandaway from and thus break the joint with the end ofthe cylinder.

The'details of constructions may be m0di-- fled as found desirable.

What I claim as my invention and desire to secure by Letters Patentis 1. In an air-cooled cylinder for internal combustion engines thecombination of an open-ended cylinder threaded externally at one end, acylinder head screwed on to the threaded end of the cylinder and formedof a: metal having a coefficient of expansion a metal which has agreater coefli-,

on to and enclosing oneiend of the cylinder and formed of a metal havinga coefficient of expansion different from that of the metal of which thecylinder is formed, and an'annular member screwed on to that part of thecylinder head which lies around the end of the cylinder completelyspaced from the cylinder and formed of a metal having substantially thesame coefficient of expansion as that of which the cylinder is formed.

3. In an air-cooled cylinder for internal combustion engines, thecombination of an open-ended cylinder, a cylinder head fitting on to andenclosing one end of the cylinder and having a coned surface formed onthat part of the head which lies around the end of the cylinder, thecylinder head being formed of a metal having a coefiicient of expansiondiflerent from that of the metal of which the cylinder is formed, and anannular member wholly mounted. and fitting closely on the conedportion'of the cylinder head spaced thereby from the cylinder and formedof a metal having substantially the same coefiicient of expansion asthat of which the cylinder is formed.

4. In an air-cooled cylinder for internal combustion engines, thecombination of an open-ended cylinder, a cylinderhead screwed on to oneend of the cylinder and having a coned surfaceformed on that part of thehead which lies around the end of the cylinder, the cylinder head beingformed of a open-ended cylinder, a cylinder head fitting on to andenclosing one end of the cylinder and having a coned surface and ascrewthread formed on that part of the head which liesaround the end ofthe cylinder, the cylinder head being formed of a metal having acoeflicient of expansion difl'erent from that of the metal of whichthecylinder is formed; and an annular member internally coned andscrewthreaded and engaging the coned and 'screwthreaded part of the headwholly spaced thereby fromthe cylinder and formed of a metal havingsubstantially the same coefficient of expansion as that ofwhich thecylinder is formed.

6.-',In an-air-cooled cylinder for internal combustion engines, thecombination of an open-ended cylinder,- a cylinder head screwed on toone end of the cylinder and having a coned surface and a screwthreadformed on that part ofthe head which lies around the end of thecylinder, the cylinder head being open-ended cylinder, a cylinder headfitting on to and enclosing one end of the cylinder and having separateconed and screwthreaded portions on that part of the cylinder head.

which lies around the end of the cylinder, the cylinder head beingformed of'a metal having a coeflicient of expansion difierent from thatof the metal of which the cylinder is formed, and an annular memberscrewthreaded internally and having a coned part adapted to engage theconed part of the head when the annular member is screwed onto the head,the annular memberbeing1 completely spaced from the cylinder by tinderhead and formed of a metal having substantially the samecoefiicient of expansion as that of which the cylinder is formed. 8. Inan air-cooled cylinder for internal combustion engines, thecombinationof an on to one end of the cylinder and having on that part of thecylinder head which lies around the end of thecylinder, the cylinderhead being eflicient 0 expansion difierent from that of e cyl- 7'open-ended cylinder, a cylinder head screwed separate coned andscrewthreaded portions formed of a metal having a cothe metal of whichthe cylinder is formed 7 and an annular member screwthreaded interua-Ilyand having-a coned part adapted to engage the coned part of the head.when the annular member is screwed on to the head,

the annular member being formed of the 7 same metal as'the cylinder andcompletely spaced thereby from 'the cylinder head.

9. In 'an air-cooled cylinder for internal combustion engines, thecombination of an open-ended steelcylinder, an aluminium cylinder headscrewed on to one end of the cylinder and having a coned surface and ascrewthread formed on that part of the head which lies around the end ofthe cylinder, and an annular member formed of steel and internally conedand screwthreaded to fit only on the coned and screwthreaded part of thehead.

In testimony whereof I have 'signedmy name to thls specification.

' GEORGE SHAKESPEARE WILKINSON.

